344 ANNUAL OF SCIENTIFIC DISCOVERY. 



ARTIFICIAL PRODUCTION OF FISH. 



WITHIN a comparatively recent period a discovery has been made 

 in France, by which fish may be produced, or breed, in lakes and 

 rivers, to an almost incalculable extent, and which is now being 

 actively prosecuted under the direction of the French Government. 

 The details of the process and discovery are as follows : Some two 

 years ago, two fishermen, named Gehlin and Reiny, of La Bresse, in 

 the department of the Vosges found that from various causes the 

 stock of trout, lor which the rivers and lakes of that department are 

 famous, greatly declined ; and they attentively studied the habits of 

 the male and female trout at spawning time, with the view, if possible, 

 of discovering the means of checking the evil. After long and patient 

 observations, they found that not one in a hundred of the eggs depos- 

 ited in the bed of the rivers, fecunded by the milt of the male, came 

 to maturity the rest being devoured by other fish, washed away or 

 destroyed by mud. They found also that of the fish which had become 

 excluded or hatched, the greater part were destroyed by the larger 

 fish of their own or different species. It then struck them that if 

 they were to collect the eggs and apply the milt themselves, instead of 

 leaving the fish to do it, and afterwards to secure the young fish from 

 the voracity of the larger ones, they would, in the course of a few 

 years, obtain an inexhaustible supply. 



Accordingly, they seized a female trout, just as they perceived she 

 was about to spawn, and by pressure on her belly, caused her to 

 deposite her eggs in a vessel containing fresh water. They afterwards 

 took a male, and by pressing his belly in the same way, caused his 

 milt to spurt on the eggs. It is by pressure on the belly that female 

 and male always relieve themselves at spawning time. These two 

 men, then, in imitation of the fish, placed the eggs on a layer of gravel, 

 which they deposited in a box full of holes. This box was fixed in a 

 bed of a flowing stream, and covered it with pebbles. The fish them- 

 selves in the natural way, cover the eggs with pebbles, and then leave 

 them. In due time the eggs excluded, and almost every one was found 

 to be good. They thus obtained from one female several hundred 

 fish. They took precautions for keeping the little creatures in water 

 where they were out of danger, and supplied them with fitting food. 

 Applying this operation the year after to a great number of fish, they 

 obtained several thousand trout ; and in a year or two more the 

 numbers had literally increased to millions. After they had stocked 



** 



the rivers and streams of the Vosges, some streams in their depart- 

 ments, the attention of Government and of the French Academy was 

 drawn to the discovery. The Academy declared that it was of an 

 immense national importance, though it had been long known to sci- 

 entific men as a scientific curiosity, not, however, as of practical utility. 

 The government on its part, saw that the application of it to the rivers 

 and streams of France would not only afford employment to a vast 

 number of persons, but would enable an immense addition to be made 

 at scarcely any expense, to the people's food. It accordingly took the 



